Merge Py Idle's changes to AutoIndent.py into EditorWindow.py since

Merge Py Idle's changes to AutoIndent.py into EditorWindow.py since
EditorWindow has incorporated AutoIndent

Rev 1.17
classifyws():  Fix a "/" to work under -Qnew (as well as without it).
Bugfix candidate!

Rev 1.18
(Already merged)

Rev 1.19
smart_backspace_event():  remove now-pointless int() call.
Bugfix candidate:  the current state of AutoIdent.py should be in 2.2.1.

Rev 1.20
Apply diff2.txt from SF patch http://www.python.org/sf/572113
(with one small bugfix in bgen/bgen/scantools.py)
This replaces string module functions with string methods
for the stuff in the Tools directory. Several uses of
string.letters etc. are still remaining.